Heins confirmed the plans in BlackBerry's fourth quarter earnings call on Thursday, indicating that at least one lower-cost device should be on the shelves by the end of September.

"The midrange BB10, as I said, expect that kind of around mid-year in various markets," Heins said, according to a transcript of the call provided by Seeking Alpha. "We're looking forward to that, because we know there's a big demand even in the midrange," he added.

The mid-year that Heins is referring to is mid fiscal year. The figures released on Thursday were for BlackBerry's final fiscal quarter of 2013, which ended 2 March, meaning that next mid fiscal year should be around the start of September.

There are no other hints as to the form factor, pricing, arrival date or any other details of the unannounced handset, but Heins confirmed it would be just one of a range of new devices in the portfolio.

"Everybody's looking at the Z10, and we are proud of the Z10, make no mistake, but we're doing much more than that. We're building a portfolio in this fiscal year, so you will see us getting into the market with various products," Heins said.

BlackBerry released the Z10 in the UK on 31 January, while the handset has only just gone on sale in some other territories, such as the US.

The fourth quarter results saw BlackBerry turning in revenue of $2.7bn, down 36 percent year on year. During the quarter, BlackBerry notched six million handset shipments, comprised of five million older devices and one million BlackBerry 10 phones. (It emerged earlier this week that supply chain company Brightstar had placed an order for one million BlackBerry 10 devices, although it's unlikely to have figured in the current figures).

BlackBerry also shifted 370,000 Playbook tablets in the fourth quarter, a form factor that Heins appears to view with some caution. He told the Australian Financial Review earlier this month: "I wouldn't want to do it the same way again, if I do something around tablets, I want it to be really substantial and meaningful, and quite frankly it would need to be profitable as well," he said.

The quarter marked a significant turnaround in profit for the company: BlackBerry posted a $98m profit over the quarter, up from a loss of $125m for the same quarter of 2012.